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The twin spark 2MTT see photo has the extra lead exiting front or on the drive end which faced the r/h side of the bike.
image5.JPG

The Twin magneto for Dominator has both leads exiting at the back in the points area, I believe the Lucas ID was a 3MTT. Most of the bits I am missing are points end.

If I had a better photo I could determine what exactly what magneto it is, might be either PAL or BTH. Its possible that the mag is being used as a generator or perhaps just the point are being used for coil ignition - all done in the day.
 

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Just read that the carbs are monobloc, these will be chopped type i.e. no float chamber. Float chamber that I can see looks like a type 14.

I see the eBay description states 2MTT well the jury is out on that detail.
 

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Not debating the value of a 2MTT versus the Manx bits and you would know better than I, but a functioning twin 2MTT must be worth a bucketload. The mag in the OP's fuzzy photo could also pass for a Scintilla. I think the one used on the Picador was along the same style.
 

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Not debating the value of a 2MTT versus the Manx bits and you would know better than I, but a functioning twin 2MTT must be worth a bucketload. The mag in the OP's fuzzy photo could also pass for a Scintilla. I think the one used on the Picador was along the same style.
£1200 will buy a good usable 2MTT.

You can buy replica 2MTT's with PVL guts for the same price. Externally they look identical but you have the normal problem associated with electronically switched ignitions namely short spark duration which isn't ideal for older combustion chamber designs.

Scintilla Magnetos - Never worked with one, I know some fitted them to Vincents. I wouldn't know one if I tripped over it.
 

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Discussion Starter #25 (Edited)
Thanks for all the info. I just received some of the documentation, tons of info very detailed. There is also mention in a letter of crossing the start finish at 130 mph 9000 rpm. It's a lot to go through, everything is there from 1963 to 1974, all the measurements, work done to the crank, valves carbs and so on also mention of 57 H.P. IMG_3531.JPG IMG_3533.JPG IMG_3532.JPG
 

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Discussion Starter #26
Nice bike I would have bought it blind - no question.

That ain't no café racer, someone spent a lot of money on that bike back in the 60's, those wheels and fork would have cost 6 months salary in 63. That's a race bike.

Front forks are manx, so are the yolks c 1957 to 62.

The wheels are also Manx, in magnesium, front is the later type 2ls from 57 to 61. The date of the rear can be determined but you need to look inside specifically the cast webs. The magnesium is Electron and is quite stable, however they should be stripped and the hubs checked for cracks, stove enamelled after and rebuilt if they are OK. If you are precious you can remove the spokes (lots of penetrating oil 1st), have them plated and use again. Manx hubs were not chromated just painted.

Swing arm is also Manx.

The mag isn't a 2MTT. Better photo please and ill be able to ID it, has a PAL look about it.

Combined oil / petrol tank isn't a good idea though lovely warm oil heating the fuel = NO.

The 650ss is a great motor when prepared well. Weak points are rods (fit steel or Titanium if you are going to use in anger). The original pistons can nip up use forged items. The original cam (X1 or later X2 which is nitrided and the same cam used in the 750 commandos) with flat foot followers is nice and torquey. Or fit a PW3 my favourite. You can fit bigger valves and bore the seats but I wouldn't, standard valves with bored seats and skinny valve contact (4 angles). Mains are strong, pay close attention to the crank, rebuild with bolt kit from Steve Maney in the Uk. Re-balance is a must.

What carbs are they? The long inlet tracks were a normal mod in period helping hi RPM breathing.

Engine breathers look like SU items.

Nice thing, as I said I would have bought it.
I will get you some pics when I receive the bike. Thanks
 

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I guess you now realise what you've got.

9000 and 130mph I don't think so - The 650ss was good or 115 in standard trim with a good motor at about 7200, Pushrod twins, especially Norton twin don't like massive revs and 9000 is way beyond engine busting territory. You should easily get 125-130mph at mid 7's with a tuned engine and a stripped out chassis. We've had the best part of 140mph on Manx gearing from a 500 domi engine. If you rev it to 9000 you'll blow it up. In standard form peak power output was around 6800ish, once the revs are past peak torque your killing the engine.

Next warning - I bet that bike has been run on Castor or "R", if it has the engine will need stripping and cleaning out. Modern castor based oils like Morris MLR40 are a blend of castor and synthetics, they don't gum up like old Castrol. Spotted a note regarding the gearbox oil in the docs published it says "30 or 40" that's R comes in two straight grades 30 and 40. So the gearbox will need stripping too. R is a one race oil, drain after and chuck it. DO NOT just fill the tank with oil and expect all to be fine, even after several flushes, the R will still be in the engine and tank. IT WILL NOT MIX WITH MINERAL AND MOST FLUSHING OILS, IT CAN EMULSIFY AND GUM and can take an epoch to dissolve even in a synthentic high detergent oil.

FINAL WARNING - Hopefully you will have owned and ridden a British bike which are nothing like a Jap, understood the vibration, the less than civil exhaust note and the even less civilised reluctance to behave themselves. They are robust things but you need to look after them. As a race bike in period it will have been stripped and checked every few meetings so I would recommend calming the engine down a bit or face regular bills. Looking at some of the chassis parts (and the ££££££'s spent) I would guess that the motor is far from standard so like for like parts will not be available. For example, if the cam is high lift you'll have heavy valve springs, you'll probably have nimonic valves in there too, all intended to support a race engine between 5000 and 8000rpm, at road speeds and lower RPM you'll be knocking the life out of cams, followers, valves and seat. The engine will be high compression somewhere between 9.5 and 11 :1 so the engine will not breath properly at low speed and the largish carbs will reduce lower rpm pick up and power delivery. Or rather you've got a ride that'll want to go 100mph everywhere with pistons and rods try to escape via the crank cases.

Will be interested to know what you do with it?
 

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Discussion Starter #28
I guess you now realise what you've got.

9000 and 130mph I don't think so - The 650ss was good or 115 in standard trim with a good motor at about 7200, Pushrod twins, especially Norton twin don't like massive revs and 9000 is way beyond engine busting territory. You should easily get 125-130mph at mid 7's with a tuned engine and a stripped out chassis. We've had the best part of 140mph on Manx gearing from a 500 domi engine. If you rev it to 9000 you'll blow it up. In standard form peak power output was around 6800ish, once the revs are past peak torque your killing the engine.

Next warning - I bet that bike has been run on Castor or "R", if it has the engine will need stripping and cleaning out. Modern castor based oils like Morris MLR40 are a blend of castor and synthetics, they don't gum up like old Castrol. Spotted a note regarding the gearbox oil in the docs published it says "30 or 40" that's R comes in two straight grades 30 and 40. So the gearbox will need stripping too. R is a one race oil, drain after and chuck it. DO NOT just fill the tank with oil and expect all to be fine, even after several flushes, the R will still be in the engine and tank. IT WILL NOT MIX WITH MINERAL AND MOST FLUSHING OILS, IT CAN EMULSIFY AND GUM and can take an epoch to dissolve even in a synthentic high detergent oil.

FINAL WARNING - Hopefully you will have owned and ridden a British bike which are nothing like a Jap, understood the vibration, the less than civil exhaust note and the even less civilised reluctance to behave themselves. They are robust things but you need to look after them. As a race bike in period it will have been stripped and checked every few meetings so I would recommend calming the engine down a bit or face regular bills. Looking at some of the chassis parts (and the ££££££'s spent) I would guess that the motor is far from standard so like for like parts will not be available. For example, if the cam is high lift you'll have heavy valve springs, you'll probably have nimonic valves in there too, all intended to support a race engine between 5000 and 8000rpm, at road speeds and lower RPM you'll be knocking the life out of cams, followers, valves and seat. The engine will be high compression somewhere etween 9.5 and 11 :1 so the engine will not breath properly at low speed and the largish carbs will reduce lower rpm pick up and power delivery. Or rather you've got a ride that'll want to go 100mph everywhere with pistons and rods try to escape via the crank cases.

Will be interested to know what you do with it?
Well now I really don't know what I'm going to do with it, if it was in boxes like the one you did I would restore it but I think it deserves to be left like it is, and the people on this forum are right it should run. I really don't want to neuter it, so maybe there is a happy medium. Your right about the cams and springs and mention of 11:1cr

I knew I read 9000rpm/ 130 mph while breezing through the paperwork, did not see the date or read the whole thing. Those numbers were from a different bike, he does mention the 650 revs to 8000 and the inlets hit the pistons around 7205 then new springs and then the exhaust floating at 7800. And thank you for taking the time to write all this info. BTW I have never owned a British bike, this should be a good one to start with. IMG_3535.JPG IMG_3536.JPG IMG_3537.JPG IMG_3538.JPG
 

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This bike will be hungry for spanners, your time and your money. I kid you not.

With all the history I would preserve it, don't restore it. However the engine and box must be stripped and cleaned out and thoroughly checked over, lower the compression to around 9.5:1 and fit standard valve springs. Make sure the clutch cush works as it should and self imposed 6800rpm rev limit and not a single RPM more. A here's why, cylinder barrels and heads are getting rare, very rare in good usable condition and bloody expensive too. The 650ss was marketed as the Manxman 1961/2 in the US and 650ss after until 67 they were most expensive 650 road burner of the day = not too common. Parts therefore can be difficult and much that comes onto the market is on the edge of scrap needing a fortune spending on it to make usable. For example a good useable cylinder say 400-600 in the UK and a down draft head 700 -1000 complete with rockers but you'll still need to gas flow and modify say another 300 - 400.

If is legal to ride a bike on the road (I guess it will be a roadster) without lights where you are located I would remove them, return the appearance of the bike to period race spec. Replace only the knackered fasteners as maintenance is a nightmare if you don't. It is possible clean up and part restore a bike without loosing character - its a simple case of picking points to lift and leaving other bits take back the over all condition, you end up with a bike that looks "looked after". I wouldn't paint anything but cut and polish and touch in. Perhaps source another exhaust system and hang the old one on the wall, many of the period race bikes used painted exhausts, in the UK I can ask a supplier to supplier without chrome and ill paint after. True the exhaust will look new but for only a few weeks.

Over the years I have had all manner of Brits from standard roadsters to factory prepared Thruxton type racers and short circuit racers. So I must say that if you've never done the British bike thing a British race bike isn't a good place to start, they can be bloody frustrating and temperamental. I think you should send the bike to me as I have the perfect spot in my garage for it!

Happy to help by typing a few words, it's as cheap as chips to do and it's a good diversion from watching moralising UK and American made crap on TV. But advice is only advice if its taken.
 

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"Hungry for spanners"..love that, I have a couple of those.

I don't know when I'll stop being amazed: a bike nut in Texas buys an odd ball British antique he knows nothing about and within a matter of hours is talking to a Brit, thousands of miles away, whom he's never met and knows the machine inside and out. Unbelievable.
 

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Never met the man...... Actually I knew that, age I think playing with grey matter.
i get it the brit shit can be knotchy specially when they put a high dome piston in a goldstar ,that is my xb33 and they just shake there hreads
cannot start it it
i actually did get it started aftern i putn in a new quadrant and the lil gear it mates to and bushed the case
the kicker grears were climbing so bad
anyway i thought the harley piston story was bullshit till i did start it up and it would ping at retarded time
hmmm 237psi kicking it oopps
turns out it was a harley piston offset pin and all
i put in a nice low dome old bsa dude up here is a gent he could not believe the dome he was all like that dog wont hunt
so yeah check it for harley pistons and maybe get some lower ratio rocker arms or slo the cam down see
but definately get it running but like jal says take out some bark
but i would try the easy way softer valve springs and maybe just ungrind the lobes knock em down
just gring a 1/16 off the peaks
file the piston dombs down a good knicker
put some warshers in the intake so it restricted to 3/4''
dont laaugh that cut down the rpm playing
lower ratio rockers would be tits
here is what a harley piston looks like in a goldstar bsa piston 80mm 3.145 001.JPG

and that was after i filed and ground a ton of stock off still had 200psi kiking though
harley pistons are striccltly for racing brit shit cant play withem ,thats all
 

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actually i have heard that a low comp harley piston out of a ww11 postal fetcher is all a brit bike can handle,and thats a flathead
so keep sharp
 

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actually i have heard that a low comp harley piston out of a ww11 postal fetcher is all a brit bike can handle,and thats a flathead
so keep sharp
I regularly run over 12:1 on racing brit engines. Photo is a modified 2 ring Manx piston for use in a pre 56 manx head compression is well over 12:1. See the squish platform on the piston? If you draw a line about half way between the top ring groove and the squish platform the section above the line is how much fits into the cylinder head at TDC. Compression isn't subtle on brit racer.

27657989_1184850784951226_953382519406133094_n - Copy.jpg

My comment with regards to the 650ss engine isn't suggesting they can't take it but rather the maintenance schedule can get rather busy and that with the higher revs required to take advantage of a big cam ad high comp pistons the valves have job to keep out of harms way.

Using a race engine on the road is a waist of money, you might take advantage of the extra horses once in a while but generally the engine is spinning at low-ish RPM and the engine works against itself. As I suggested earlier, stock springs and lower comp pistons around 9 to 9.5:1 is all you need to change and lower red line to around the peak torque point. With some confidence I can say the original race pistons will not be replaceable anyway, just put them in the heritage box.
 

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I regularly run over 12:1 on racing brit engines. Photo is a modified 2 ring Manx piston for use in a pre 56 manx head compression is well over 12:1. See the squish platform on the piston? If you draw a line about half way between the top ring groove and the squish platform the section above the line is how much fits into the cylinder head at TDC. Compression isn't subtle on brit racer.

View attachment 89330

My comment with regards to the 650ss engine isn't suggesting they can't take it but rather the maintenance schedule can get rather busy and that with the higher revs required to take advantage of a big cam ad high comp pistons the valves have job to keep out of harms way.

Using a race engine on the road is a waist of money, you might take advantage of the extra horses once in a while but generally the engine is spinning at low-ish RPM and the engine works against itself. As I suggested earlier, stock springs and lower comp pistons around 9 to 9.5:1 is all you need to change and lower red line to around the peak torque point. With some confidence I can say the original race pistons will not be replaceable anyway, just put them in the heritage box.
im know where you are man and agree with all its common good sense
i like to jkeep you spilling so i can learn more,see
but my harley piston story is true why i brought it up its funny
i just figured they were full of shit

i clayed that harle=y piston that was in my bsa
it was like nothing even much for squish i cant remember but there was never a hundrerd thousanths anywhere in that lashup and scary close too less than .025'' in many areas 250 psi kicking alky motor huh lol
it was all new bore never had run my bsa old guy up here had a nice almost flat top piston for it and rings

i have run that and its very easy starting cold or hot i can usually 1 kick start it cold or hot if not then it takes 3
now i wish it had just a bit more cr it feels a bit flat
meanwhile 3 bsa chair.jpg
 

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The magneto is one sold by Joe Hunt at one time. I have the same mag that used to be on a Norton race-bike. The only difference on my mag is the finned cover actually says "Joe Hunt" on it, probably just an earlier or later run of castings. I e-mailed Hunt about it a number of years ago and they did not have much to say about it except that if I wanted replacement parts for it that they would have to see the mag or good photos of it's points etc. before they could tell me if they could supply them.

I agree that the bike should be kept as original as possible as a tribute to it's past builders/owners. I used to talk to Edward Bilton-Smith about Norton bikes and he sent me a lot of photos of his old bikes and him racing at one point a number of years ago. This bike is not his original racer from the early 60s that he won a championship on, but I think it originally belonged to a friend of his back then and he must have later ended up with it, and maybe he did work on it. Ed's original racer was one of the blue-Manxman bikes. He first raced it in almost standard trim with all it's street cycle-parts and blue paint, as time went by he ditched more and more of the original bike and in it's last version all that was left was the 650cc engine/gearbox stuck into a mid-50s Manx rolling chassis. After Ed won the championship with the blue Manxman, at the last race he let a competing rider take it for a lap and that rider blew the engine to pieces on a back part of the track were he was out of everyone's sight, Ed was sure he did it on purpose so he did not have to race against it anymore, for quite some time nobody could stay with Ed no matter what bike they rode against him with.

A local bike-shop bought that 650cc racer with the blown engine from Ed and they were pissed because there were no racing parts in the engine, Ed had just blueprinted the engine and modified the stock parts so they worked much better, he also did lots of testing at the drag-strip to get the exhaust and intake-tract length optimized which he said made a big difference in power. He won lots of drag-racing trophies with the bike too. He never saw the bike after he sold it, it did not get put back together and get back on the track, the shop could not duplicate Ed's engine-building skills, he was an expert machinist and a smart guy to boot.

The old photo I have of this bike shows it with street lighting and equipment still on it, so at a later point in time, maybe after Ed got it he turned it into a racer and modified the engine for racing.

This could be the last existing bike and engine that is intact that Bilton-Smith tuned back in the day, so it certainly is more important than the wishes and whims of any present and future owners of the bike, maybe Ed's son would like to have the bike? Lots of time should be taken deciding what to do to the bike to preserve it and it's history. If some butcher gets their hands on the engine and bike they may damage it or erase some details that will be lost forever, and that would be a shame. I certainly would not let Paul Zuniga get his hands anywhere near it until you call known expert Jim Comstock and ask him what he thinks about Mr. Zuniga as a Norton mechanic.
 

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"Hungry for spanners"..love that, I have a couple of those.

I don't know when I'll stop being amazed: a bike nut in Texas buys an odd ball British antique he knows nothing about and within a matter of hours is talking to a Brit, thousands of miles away, whom he's never met and knows the machine inside and out. Unbelievable.
indeed it is really amazing and pretty bitchen to witness
the internet and these forums for like minds make it possible to share knowledge that otherwise might not get exposed
a glorious use in my opinion

and this shit is real ,its hard to describe i am just glad i can read along and at 60 continue to learn
shit its not like there are 1,000 jalsteve's out there, ill bet there is very few with his depth of expertise maybe only 5 or 20 above ground , i dunno

but how many are willing to share ? thats the real shining part, my hats off to you jalsteve:cool: you are one cool cat,man...
keep it coming i am much obliged
while i am at it can you, tell if my goldstar cams are just super mild by a real good image of the lobe ?
see when i got the cycle i went thru the timing chest making sure all was happy took good pics
gearbox as well it was my first britbox,i found it a lot like a bultaco trans or an automobile gearbox
i guess i could just look at images of db34 cams and what not but i would rather keep you talking,thats all
 

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Your cams should be marked, if not you'll need to measure lift and duration but figures can vary due to wear and tear or just buy a new set to be sure. Vernier cams work well for perfect timing you can also alter timing to suit riding style or conditions. Goldies are notorious for not starting hot or cold. I have found that induction is lazy and the plug is often a dry as a bone despite carb/float flooding and kick priming. Remember cam form is a combination of cam, follower and rocker ratio.

Most British gearboxes are car like.
 
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